Uploading .bak files are being corrupted

I am uploading a .bak file using WinSCP, but when I verify the .bak file, I get an error that says the file is not a valid microsfot tape format backup set. I think WinSCP is corrupting the .bak some how. Help please.

The error I get in SLQ is:

Msg 3242, Level 16, State 2, Line 1
The file on device 'C:\Backup\backupdata02072023.bak' is not a valid Microsoft Tape Format backup set.
Msg 3013, Level 16, State 1, Line 1
VERIFY DATABASE is terminating abnormally.

Make sure you are using Binary transfer mode.
If this does not help, please post session log file.
Did you check how is the file modified?